Substituted cyanoiminoimidazolidines and -tetrahydropyrimidines useful as pesticides

Abstract

Novel substituted pyridylmethyl-cyanoiminoimidazolidines and pyridylmethyl-cyanoiminotetrahydropyrimidines of the formula ##STR1## in which R 3 is hydrogen or C 1 -C 4 alkyl; A is a --(CH 2 ) 2 -- or --(CH 2 ) 3 -- radical; X is halogen; and n is an integer 0, 1, 2 or 3; and the salts of compounds of formula I. Also described is a process for the preparation of these compounds, the corresponding starting materials and intermediates, and the use of the novel compounds in pest control, especially for controlling insects and representatives of the order Ararina, particularly insect pests in rice crops.

What is claimed is: 
     
       1. A compound of formula I ##STR8## in which R 3  is hydrogen or C 1  -C 4  alkyl; A is a --(CH 2 ) 2  -- or --(CH 2 ) 3  -- radical; X is halogen; and n is an integer 0, 1, 2 or 3; the salt of the compound of formula I. 
     
     
       2. A compound of formula I according to claim 1, wherein R 3  is hydrogen or methyl; X is chlorine and n is an integer 0, 1 or 2. 
     
     
       3. A compound according to claim 1, wherein n is the integer 0. 
     
     
       4. A compound of formula I according to claim 1, wherein R 3  is hydrogen, methyl or ethyl; and n is the integer 0, 1, 2 or 3. 
     
     
       5. A compound of formula I according to claim 1, wherein R 3  is hydrogen. 
     
     
       6. A compound of formula I according to claim 1, wherein the pyridyl radical is a pyrid-3-yl or pyrid-4-yl radical. 
     
     
       7. A compound according to claim 6 of formula ##STR9## 
     
     
       8. A compound according to claim 6 of formula ##STR10## 
     
     
       9. A compound according to claim 2 of formula ##STR11## 
     
     
       10. A compound according to claim 2 of formula ##STR12## 
     
     
       11. A composition for controlling insect pests and pests of the order Acarina containing as active component at least one compound of formula I according to claim 1. 
     
     
       12. A method of controlling insects and representatives of the order of Acarina which comprises bringing into contact or treating the pests, or various stages of development thereof or the locus thereof, with a pesticidally effective amount of a compound of formula I according to claim 1. 
     
     
       13. A method according to claim 12 for controlling feeding insect pests in rice crops.